Calibration is an important method to ensure the accuracy and reliability of the acceleration sensors measurement results. Aiming at the problems of the insufficient memory and slow processing speed caused by excessive data volume in low-frequency calibration with existing calibration methods, the research of a low-frequency accelerometer calibration system based on homodyne laser interference is developed. The error compensation method is proposed by analyzing the nonlinear error, especially the non-orthogonal phase error. By using the dynamic successive phase unwrapping method and the self-adaptive dynamic decomposition algorithm for data acquisition and processing, the goal of reducing the sampling rate and the data volume is achieved, and the calibration accuracy is ensured. The experimental results demonstrate that the system can achieve high-accuracy sensitivity calibration of the accelerometer in the frequency range from 0.1 to 80Hz and satisfy the test requirements of low frequency calibration.